DESCRIPTION: (Applicant's Description) Smoking in children and adolescents has been shown to be associated with mental health problems such as hyperactive disorder, attention deficit disorder, depression, and learning problems. Three conceptually distinct processes may account for these associations. There may be a direct causal relation between mental health problems and smoking; children with mental health problems may experience social influences that may in turn account for their higher propensity to smoke; or, mental health problems and smoking may be explained by a common underlying factor. Each one of these distinct processes has different implications for designing effective interventions to prevent smoking. We will conduct an investigation of the nature of the association between three early childhood mental health problems - high levels of hyperactivity or attention deficit disorder, high levels of depressive/anxiety symptoms, and severe achievement problems- and patterns of smoking between ages 11 and 18. We will establish the independent effects of these three early childhood mental health problems and their combined or comorbid effects on smoking in late childhood and adolescence. Furthermore, we will investigate race/ ethnicity and gender differences in the effects of early childhood mental health problems on smoking in adolescence. We will develop Latent Growth Models portraying the age patterns of propensities to smoke. These models will establish and simultaneously account for (I) direct effects of childhood mental health problems on smoking; (II) effects of early familial conditions that may impact both mental health and smoking; and, (III) intervening effects of social influences that may mediate the effects of childhood mental health problems on smoking. To accomplish these goals, we will use extact data from the National Longitudinal Survey of Youth. These data uniquely address the objectives of the proposed study in that childhood mental health assessments precede the ages when smoking initiation occurs. In addition, measures of a broad set of early familial conditions and social influence factors are available and these measures allow us to address the net direct effects of mental health problems on smoking. Finally, the study sample includes large subsamples of African American, Hispanic and white children, allowing us to address the question of gender and race/ethnicity differences in the association between childhood mental health problems and smoking. If there are direct and substantial effects of childhood mental health problems on adolescent's smoking, then targeted intervention programs may be wanted for children with specific mental health problems. Moreover, clinical and physiological studies may be called for to understand the processes specific to these conditions that lead to initiation of smoking and development of nicotine dependence.